Variable unit pressure muller



SePt- 15, 1952 R. L. MolLvAlNE 2,610,802

2 sm'rs-SHEET 1 fz: Veni 471-' E019 eri/L. Nall va/ze EH fi/4. yal/M5sept. 16, 1952 R. 1 MlLvAlNE 2,610,802

VARI-ABLE UNIT PRESSURE MULLER Filed Sept. 14, 1948 2 SHEETS-SHEET 2z/EUUJ" Robert' L. Nall zfqzze Patented Sept. 16,` '1952 VARIABLE UNITPRE-SSR MJL Robert L. Mcllvaine, Glencoe, Ill., assigner, by

mesne assignments, to HerbertSimpson Corporation, Chicago, Ill., acorporation of Illinois Application September 14, 1948,*Serial No.49,229

' y 1 claim. (o1. 241+1s2) This invention relates to improvements inmulling machines.

More particularly it has to do with a novel type of mulling machinewherein the pressure exerted by the muller wheels on the material beingworked in the crib thereof is controlled by mechanical means actingthrough the muller wheels.

In the mulling of materials such as sand or sand mixtures high unitpressures are desirable to efliciently mix and work the material. Thesepressures are usually achieved by varying the weight of the mullerwheels. -However, some materials, particularly light bodies such as airfloated clays, do not set up enough frictional resistance to the mullingoperation to causethe muller wheels to rotate. Thus, it is desirablewhen working such materialsto use light mullers with low inertia valuesand attain high unit muller pressures through mechanicalmeans actingthrough the muller wheels. y

It is, therefore, an important object of the kpres-- ent invention toprovidev a mulling machine wherein themuller wheels `have a low inertiavalue and wherein high unit mulling Vpressures are attained through useof a mechanical means other than' the muller wheels themselves.

A further object of the present invention is to provide a muller inwhich fluid actuated power cylinders are used in conjunction with themuller wheels to control the amount of unit pressure applied against thematerial being processed.

Another object of this invention is the provision of means for varyingthe unit pressure exerted on the material being mulled while the machineis in operation. n y

According to the teachings of thel present invention there is provided aset of muller wheels of relatively light weight pivotally mounted fromthe crosshead or turret of a mulling machinejfor rolling movement in acircular path on thefbed-` plate of the machine. The turret is rotatedby a power driven center vertical shaft. A doubleacting Huid-actuatedpower cylinder is rigidly mounted on an upper tubularfextension of theturret so that its downwardly extending'piston rod bears against an armmember which extends substantially axially from the muller wheel. Afluid, such as air or oil, is brought byfmeans of a center tube and arevolving fluid type joint to a distribution control boxmounted on theupper tubular extension of the turret. The valves in the control box maybe suitable operated by an electrically operated control valve locatedadjacent' the control box and supplied with elec.-

trical energy by means of a commutatcr mounted on the upper end of thetubular extension.

` When iluid is applied to the top of the power cylinder, pressure isexerted directly downwardly against said axially extending arm causingthe muller wheel to be pressed downwardly against the material in thecrib 'with any unit pressure up to the'pressure capacity ofthe fluidcylinder. When fluid is applied tothe lower e'nd of the power cylinder areverse pressure is applied to the axial extending arm which tends toliftthe muller away from the bedplate of 'the machine and it may be soregulated as to move the muller wheel completely out of the materialbeing worked.y

Other and further features, advantages and objects of the' presentinvention will be readily apparent to those skilled in the art from thefollowing ydetailed description of the annexed sheets of drawings` f Onthe drawings: y

Figure 1 is a top planv view of the mulling machine constructedaccording to the teachings of the present invention.

'Figure 2 is a vertical sectional view taken substantially on line II-IIin Figure l.

As shown on the drawings:

In Figures 1 and 2, the reference numeral I0 indicates generally amulling machine including a crib having a flat base plate II of circularconfiguration having an upstanding flange I2 extending around theperiphery of the plate. ,y A

` cap screws I5. This secondary plate is made of a special wearresistant material as also is a wear plate I8 disposed on the base plateI I,

A tubular bearing support housing. I9 is secured by cap screws 20 in anopening 2I in the base plate II and in the wear plate I8.

'Rotation of the mulling apparatus is carried out by a drive shaft 23,which is journaled'in roller bearings '24 at the lower end of thesupport housing I9 and is driven by an electric motor 25 through a geardrive 26. At its upper end, the drive shaft is keyed to a turret 21which is supported on the housing I9. Thus, as the shaft 23 is rotatedthe tur-ret 21 is also rotated. An arm 28, Figure l, extends outwardlyfrom a sleeve portion 29 formed integral with the turret 21 to support ascraper holder- 30 at the lowerend of which a scraper and plow member 3|is secured by cap screws 32.

The scraper is arranged to scrape material from the side and bottomwalls of the crib and direct it inwardly toward the center of the crib.As the material moves inWa-rdly it is toppled over the inner end of thescraper blade, the height of which decreases progressively toward itsinner end.

As seen in Figure 1, a sleeve portion 33 on the turret 21 has an arm 34projecting outwardly therefrom to support, through bolts 35, a curvedplow blade 3G. This plow blade is arranged at its innermost end 36a toscrape material from the support member I9 and is curved to urge thematerial outwardly as the turret rotates in the crib. The blade of theplow is of a height at its outermost portion 36h to permit material totopple thereover as the turret rotates, providing ,a zone in whichmaterial is in a loose tumbled condition.

Oppositely disposed in the crib of the machine and arranged to rotatewith the turret 21 is a pair of conventional muller wheels 40. Themuller wheels are pivotally mounted on the turret 21 by means of supportarms 4| which have sleeve portions 42 pivotally mounted on axles 43carried by the sleeve portions 29 and l33 of the turret. The supportarms 4l also include an inwardly projecting arm 44 integrally formed onthe support arms 4| and abutting at their inner ends on shims 43, Figure2, positioned on a shoulder portion 45 of the turret 21 to limit thedownward pivoting of the muller wheels. An inner sleeve portion 41 ofeach support arm is arranged to receive a muller wheel shaft 48 aboutwhich the muller wheels 40. revolve as the turret rotates.

T remove material from the crib there is provided a discharge door l inthe floor of the crib. The door may conveniently be made in the shape ofa sector of a circle, fitting in a closed position into a mating opening52 in the wear plate I8. The door is opened by pivoting it on a hinge 53by means of a handle54. When the door is opened, rotation of the plowand scraper will cause material to be pushed through the door opening.

In accordance with the teachings of this invention, a tubular post 60 ismounted over thc vertical drive shaft 23 with an apertured end closureplate 5l disposed over the reduced threaded upper end of the shaft 23,and held thereon by a washer 63 and lock nut 64. A bracket 66, securedacross the upper end of the post 60, as by welding, is provided withdepending arms 88 on the bottom surface thereof. A uid actuated powercylinder 1D is pivotally connected on a pin 1| through each of the arms68 having a piston rod 13 extending directly downwardly for pivotalconnection with the arm 44 of the muller therebelow.

It is to be particularly noted that the piston rods 13 exert asubstantially straight vertical thrust on the arms 44 and that the arms44 are attached directly to the rocker arms 4l substantially at the hubportions of the mullers. Thus the thrust from the power cylinders isapplied through the muller wheels to the material being processed in thecrib.

Power is supplied to the fluid cylinder by means of a fluid tightrevolving joint 16 of any standard construction, which permits a portionof the joint in the bracket 65 to revolve with the bracket while thesupply line 11 thereabove remains stationary. A supply line 18 insidethe tube 60 delivers the huid, either a gas or a liquid, to a controlbox 80 which is also conveniently 4, mounted alongside the tubularextension bolt 60. Since the power cylinders 10 are double acting,supply lines 82 direct fluid to the top of each cylinder while supplylines 83 deliver Iluid to the bottom of each cylinder. It will beunderstood, of course, that the standard valve arrangements necessaryfor the operation of a double-acting cylinder will be incorporated inthe control box 80.

The selective delivery of nuid under pressure to the various supplylines may be controlled by an electrically operated valve member (notshown) which is energized by electrical supply lines 84 and 85 through arotating commutator (not shown).

The control box, the electrically operated valve and the commutator maybe of any standard commercial design.

From the foregoing description it will be recognized that there isprovided in this invention a simple, eiiicient means for varying theunit mulling pressure exerted on material being processed in the cribWithout using heavy muller wheels which have high inertia values.

In operation, when pressure is applied to the topV of the power cylinder1D it will be transmitted to the material in any predetermined quantityup to the limit of capacity of the cylinders.

When pressure is applied to the bottom of the cylinders the piston rods13, through their pivotal connection to the limit arms 44, will pivotthe muller wheels away from the wear plate of the crib thussubstantially lessening the pressure exerted thereon.

It is contemplated that the device of the present invention will be usedfor processing materials ywhich at some stage during the process reach aconsistency where either heavy unit pressures are not desirable or theheavy mullers with high values will not turn.l It is possible, with thearrangement described above, to raise the mullers during the initialstage, sov that a simple mixing action by the plows is obtained. At theproper time the mullers could be allowed to bear on the material withincreasing pressure until the maximum desired unit pressure is reached.This arrangement would be particularly desirable for materials such asfoundry oil bonded core sand, wall paper coatings, air floated clay, andthe like.

It will, of course, be understood that various details of constructionmay be varied through a wide -range without departing from theprinciples of this invention, and it is, therefore, not the purpose t0limit the patent granted hereon otherwise than necessitated by the scopeof the appended claim.

I claim as my invention:

A muller comprising a crib, a housing extending upwardly through thecenter of said crib, a turret rotatably mounted on the top of saidhousing and projecting upwardly therefrom, power means beneath Vsaidcrib for rotatably driving said turret, parallel horizontal sleevemembers spaced outwardly from opposite sides of said turret and forminga part thereof for rotation therewith, oppositely projecting axlescarried by said sleeve members, a wheel support arm pivotally mounted eneach of said axles and extending inwardly therefrom along said turret, amuller wheel axle mounted on the free end of each of said wheelsupporting arms and extending outwardly therefrom, muller wheelsrotatably mounted Von each of said last mentioned axles for rotationabout parallel spaced axes adjacent but on opposite sides of a diametralline intersecting the center of said turret and moved about said crib byrotation of said turret, a bracket on said turret above said larms andextending in opposite directions, a separate double acting fluidpressure cylinder pivotally connected to said bracket adjacent each endthereof and depending therefrom, actuating rods depending from saidcylinders for extension or retraction with respect thereto upon theadmission of iiuid under pressure to one end or the other of saidcylinder, said Wheel supporting arms having connecting arms projectinginwardly therefrom ytoward. said turret, and pivotal connections betweensaid actuating rods and said inwardly projecting connecting arms. 1

ROBERT L. MCILVAINE.

6 REFERENCES CITED The following references are of record in the file ofthis patent:

' UNITED STATES PATENTS`

